<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title>实验2_3</title>
		<style>
			.c1 {
				border: 1px dashed limegreen;
				width: 500px;
				margin: 10px;

			}
			.c2 {
				padding: 20px;
				text-align: center;
			}
		</style>
	</head>
	<body>
		<div class="c1">
			<div class="c2">内容</div>
		</div>
	</body>
</html>